use version 1.2.1-scm1 of apache shiro to fix issue #331

--HG--
branch : issue-331
added scm.home example for windows

--HG--
branch : issue-328
close branch issue-328

--HG--
branch : issue-328
extra : close : 1
merge with branch issue-328
fix license headers
util classes should be final with a private constructor
remove unused fields
update web-compressor plugin to 1.4
merge with branch issue-331
disable directory listings on default scm-server configuration
fix eager singleton loading
protect mustache resources
respect subscriber annotation on event bus registration
register every injectable object to event bus

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rename : scm-webapp/src/main/java/sonia/scm/ScmSubscriberModule.java => scm-webapp/src/main/java/sonia/scm/ScmEventBusModule.java
enable tab scrolling for repository setting tabs
fix license headers
[maven-release-plugin] prepare release 1.28
[maven-release-plugin]  copy for tag 1.28
[maven-release-plugin] prepare for next development iteration
fix wrong handling of git file hooks

--HG--
branch : issue-339